The present invention relates to the use of a solution of a gelatin derivative in combination with at least one amino acid, if desired in the form of a pharmaceutically acceptable salt or carboxylic acid derivative, for the preparation of a composition for inhibiting renal uptake of substances, that are potentially damaging for the kidneys, in a living being.
Radionuclide labeled peptides and also monoclonal antibodies or their fragments and other compounds like certain antibiotics or chemotherapeutic agents undergo undesired renal uptake and cellular retention leading to a high kidney radiation dose or concentration. Increased amounts of protein or raised doses of radiation or toxic substances in the kidneys may eventually lead to kidney damage.
In the patent publication EP 0094378 (PCT/EP00/06917) it has been described that co-administration of non-target substances, like lysine in combination with arginine, can reduce non-target kidney retention of immunoconjugates, metabolites thereof and other substances that are potentially damaging to the kidneys, such as defined above.
Recently it was published that the gelatin-based plasma-expanders Gelofusine® (B. Braun, Germany) and Haemaccel® result in tubular proteinuria. Such gelatine-based solutions are used in clinical medicine in hemorraghic and septic shock to control blood pressure levels, as well a in the post-surgical situation. Gelofusine is a synthetic colloidal solution based on bovine bone-derived gelatin, and may be considered as a gelatine-based plasma expander. Haemaccel is a synthetic colloidal solution of urea cross linked degraded gelatin. It was also published that Gelofusine could successfully been applied to reduce kidney uptake of radiolabeled octreotide to a level comparable to that of lysine. At present it is not clear by what mechanism gelatin-based plasma expanders inhibit kidney uptake of radiolabeled octreotide.